Fix grid overlay toggle - sync with MijickCamera's built-in grid

- MijickCamera's grid defaults to ON (true)
- Add setGridVisibility() call in onAppear to sync initial state
- Add onChange handler to update grid visibility when setting changes

SelfieCam/Features/Camera/Views/CustomCameraScreen.swift

@@ -164,6 +164,8 @@ struct CustomCameraScreen: MCameraScreen {
             lastMagnification = zoomFactor
             // Track initial camera position
             currentCameraPosition = cameraSettings.cameraPosition
+            // Sync grid visibility with MijickCamera (defaults to true, so we need to set it)
+            setGridVisibility(cameraSettings.isGridVisible)
         }
         .onChange(of: cameraSettings.cameraPositionRaw) { _, newRaw in
             // Switch camera when position changes in settings
@@ -185,6 +187,10 @@ struct CustomCameraScreen: MCameraScreen {
             // Only update when sync setting changes, not on every color change
             updateFlashSyncState()
         }
+        .onChange(of: cameraSettings.isGridVisible) { _, newValue in
+            // Sync grid visibility with MijickCamera
+            setGridVisibility(newValue)
+        }
         .onChange(of: cameraManager.capturedMedia) { _, newMedia in
             // Directly observe capture completion - bypasses MijickCamera's callback issues
             if let media = newMedia, let image = media.getImage() {